The alcohol in beer acts as a solvent for a variety of aromatic compounds; therefore, when it is eliminated, as in non-alcoholic beers, the final product loses aromas and some of its taste. It is difficult to recover these compounds.
Researchers from the University of Valladolid (Spain) used a special beer (with 5.5 percent alcohol) and another reserve beer (6.5 percent) from which they extracted three aromatic compounds using a pervaporation process.
Carlos A. Blanco, one of the authors, said that their technique consists in using a semipermeable membrane to separate two fractions from alcoholic beer: one liquid phase in which alcohol is retained, and another gaseous phase, where the aromatic compounds come in. Then, this gaseous phase can be condensed, the aromatic compounds extracted and added to non-alcoholic beer.
The researchers added these substances to two 'almost' alcohol-free beers on the market: low-alcohol beer (less than 1 percent ABV) and alcohol-free beer (less than 0.1 percent ABV).
The researchers have recognized that this technique cannot yet capture all the aromas and tastes associated with alcoholic beer , but it does show progress in making 'alcohol-free' varieties more palatable for the consumer.
The study was published in the 'Journal of Food Engineering'.